Whatcha lookin’ at? The attention of crowds shows no tipping points

Researchers sent people into crowded environments, asking them to stare at a …

It's a familiar experience: you're walking through a crowded area, when you spot someone staring intently at some distant spot. Do you stop to look as well? How long do you look if there's nothing obvious there? Early research had suggested we often do stop to look, and as more join in on the stare, the crowd will eventually reach a tipping point, with the vast majority of its members staring off in the same direction. Now, researchers have revisited the question with modern imaging technology, and found that there isn't a tipping point. In fact, in circumstances where some terrorism-obsessed authorities say we should look, men actively avert their gaze.

The original experiments were done back in the 1960s, using the streets of New York as a lab. It had suggested that crowds show a tipping point behavior (also referred to as "crystallization"). Once a sufficient fraction of the group started to stare, nearly everyone would follow along.

In the new work, the authors turned to the streets of Oxford (where some of the team was based) and updated the techniques, using high-resolution video imaging and a computer analysis that figured out the vectors that described pedestrians' gazes and direction of motion.

The video camera was perched high above a specific area of a shopping street. The authors worked with a set of assistants who, on cue, would all stop within a small area of the street and stare up at the camera. In different experiments, the assistants were sent out in groups of various sizes, anywhere from a lone staring individual to an entire group of 15 that would all stop and stare at once. Afterward, the video was analyzed to figure out how many of the surrounding pedestrians stopped and stared along. All told, over 2,800 pedestrians were present during various iterations of the experiment.

Maybe we've become more indifferent, or maybe the British hate to stare, but the new researchers saw nothing like the contagion of attention seen back in the 1960s. Instead of drawing in nearly 90 percent of the crowd, attention maxed out at somewhere around half the surrounding pedestrians. And there was no tipping point. Instead of a sudden leap in attentiveness, the fraction of pedestrians staring along went up gradually in direct proportion to the number of assistants sent out to stare. The more people that stared initially, the more likely others were to join in.

There was no indication that there was a saturation point—that is, the numbers were still going up when the researchers reached their cutoff point of 15 assistants staring at once. One trend that was apparent, however, was that slower-moving pedestrians were more likely to follow the gaze of the assistants. There are plenty of reasons why this might be the case (more time to notice the assistants, less pressing matters on their minds, etc.), and the authors weren't able to discriminate among them.

The next set of experiments seemed to have been informed by the age of terrorism. Two men were sent either back to the shopping street or into a train station; one scribbled notes on a hand-drawn map, while the other used a videocamera as if he were getting images of the surroundings. This is exactly the sort of thing we're supposed to report to the local constabulary as suspicious activity. (As a control, two men were sent to stand near each other, but not interact or perform any actions.)

On the shopping street, the pair did attract a bit more attention, primarily from those closest to them. As pedestrians passed further from them, they were more likely to ignore them. By the time a pedestrian was further away, they were no more likely to look at the suspicious behavior than they were at the individuals in the control situation.

Something else entirely happened in the train station. Here, the control pair attracted a fair bit of attention from those closest to them, with that attraction again fading by three meters. But for the pair doing suspicious things, the exact opposite was true: those closest to them were likely to avert their gaze. Within a meter, essentially nobody looked at the pair, and things only matched the attention given the control pair by 2.5 meters.

Perhaps even more oddly, this lack of attention was driven nearly entirely by males. The authors speculate that men were concerned that an aggressive stare would be seen as a challenge, and would provoke a confrontation.

Overall, the authors conclude that, at least as far as where to direct our attention, we humans don't engage in spontaneous group decision-making. They note that there are indications we do in other circumstances—they cite the fact that people tend to cross the road in a group that often includes members who are largely unaware if doing so is actually safe. What they can't distinguish is whether the shared attention they do see is a matter of social conformity (staring along to fit in) or if there's an expectation that staring will provide some valuable information.

All of this leaves lots of room for further experiments. I expect exit interviews of random pedestrians who inadvertently ended up being part of an experiment to follow shortly.